We've stayed a few times at this WalMart. The parking lots is very large and the entire east side was been open when we stayed. Several other RVs stayed as well. It's quite and a great place to stock up on supplies.
We have observed that WalMarts are sometimes in areas controlled by municipal rules that forbid overnight parking. Generally, if the municipality doesn't forbid overnight parking, then WalMarts are friendly to RVs boondocking. I use the AllStays "ONP WalMart" app to check and have found it's about 90% reliable, however we have arrived at WalMarts that the app said were ONP friendly, but displayed "No Overnight Parking". I have contacted Allstays about those Walmarts and they did change the app to reflect that Walmart to no longer be overnight parking friendly. It's always better check the app AND call ahead or go in and ask if it's ok to park there.